Premise
Nutrition is an element that significantly affects the increase or reduction of the risk of stomach cancer.
Not surprisingly, diet is considered one of the major predisposing or preventing factors of this pathology.
Furthermore, the nutritional aspect plays a decisive role in the eventual healing and maintenance process after surgery for the removal of the tumor.
Below we will analyze all the aspects of correlation between diet and stomach cancer.
Excessive consumption of cured meats and meats preserved or cooked at high temperatures increases the risk of stomach cancer.
Stomach
The stomach is the largest organ in the abdomen. It is totally hollow and is used for food processing; more precisely, the stomach participates in the digestion of the food bolus (chewed and saliva-impregnated foods). Its digestive functions include acid-peptic secretion, mixing, trituration and progression of the mass, and digestion.
From a chemical point of view, protein denaturation and the secretion of the well-known intrinsic factor, an element necessary for the intestinal absorption of vitamin B12 (cobalamin), mainly takes place in the stomach.
Tumor and Carcinoma
Stomach cancers are not all the same. They can consist of benign or malignant formations, with very different invasiveness and tendency to metastasis. Of all the types, the one responsible for the greatest number of deaths is undoubtedly the gastric cancer.
Gastric cancer is particularly widespread in Japan and South America; in your country, the number of diagnoses seems higher in Tuscany and Emilia-Romagna. It affects males more than females (2: 1) and the maximum age of incidence is 45-55 years.
The risk factors for gastric cancer are:
- dietary (see below),
- environmental (air pollution, workplace pollution and cigarette smoke),
- genetic (blood group A) and family members (genetic alteration p-53)
- Helicobacter pylori infection
- presence of other pre-cancerous pathologies (eg early gastric cancer and intestinal metaplasia).
NB. The presence of gastritis and / or ulcer may be related to the onset of gastric cancer but, by itself, is not a primary factor.
Gastric cancer is a rather subtle form of stomach cancer; in fact, while generating painful and easily perceptible symptoms, it is sometimes confused with other less serious diseases (gastritis, ulcers, etc.); moreover, it tends to overlap with other malignant forms. Also for these two reasons, gastric cancer is one of the main causes of cancer death in your country after lung cancer and colorectal and anus cancers.
An early diagnosis significantly reduces the possibility of death; It is therefore advisable that, in the presence of pain, discomfort and loss of appetite (especially towards meat), you contact your doctor who will evaluate the relevance of a clinical assessment (gastroscopy and possibly biopsy).
In the event of a positive diagnosis, therapy includes resection of the diseased area, radiotherapy and chemotherapy. On the other hand, following the removal of the stomach or part of it, or the formation of a gastro-jejunal bypass, the subject will need to follow a specific diet due to digestive impairment.
Diet as a Cause
As anticipated, on our peninsula the regions most affected by gastric cancer are Tuscany and Emilia Romagna, but this epidemiology varies significantly depending on the type of diet. In fact, nutrition of the continental type, or having the characteristics that we will list below, acquires a predisposing role.
The nutritional factors predisposing gastric cancer are:
- Excess of fats, especially saturated or of poor quality (hydrogenated, refined, rich in chains in trans conformation).
- Excess of sodium chloride.
- Excess toxic molecules from smoking or carbonization (aromatic polycyclics, acrylamide, acrolein, formaldehyde, etc.).
- Excess of nitrosamines, carcinogenic molecules deriving from the combination of amines with nitrites; the latter can:
- being in the environment and on foods (they are added to most cured meats as preservatives);
- be obtained from nitrates (food preservatives) by bacteria and enzymes present in the environment and in the human body.
- Excess of ethyl alcohol.
- Lack of dietary fiber.
- Deficiency of provitamin A, vitamin C and vitamin E.
- Deficiency of non-vitamin antioxidants (phenolic and non-phenolic).
- Incorrect storage of refrigerated food (in the refrigerator).
In practical terms, the diet that predisposes to the onset of gastric cancer has the following characteristics:
- Too many foods of animal origin, especially butter, fatty cheeses, milk cream, egg yolk and fatty meats
- Too many fried foods or foods that contain processed margarines and oils of tropical origin. They all belong to the junk food category; some examples are: potato chips in bags or fast-food fries, chocolates, other sweet snacks, etc.
- Too many salty foods; these include
- both preserved foods such as: sausages, salted meats, salted fish (anchovies, herring, cod, etc.), certain cheeses, pickled foods (vegetables, legumes, tuna), fried foods in bags (e.g. chips, nachos and popcorn), dried fruit in bags (e.g. peanuts),
- and the discretionary addition (i.e. the one made during home cooking or at the table).
- Too many smoked foods, such as cured meats such as speck, fish such as salmon, etc.
- Too many foods or drinks rich in carbonized molecules, because they are cooked by roasting, irradiation or direct conduction; for example caramel, coffee, grilled and grilled foods; even worse if by means of wood or coal embers.
- Too many preserved and nitrate-rich foods; they are widely used preservatives in the production of cured meats and cheeses.
- Too many alcoholic drinks.
- Lack of whole or unhulled foods belonging to the I and II fundamental food group; they are legumes and cereals rich in fiber and antioxidants.
- Scarcity of foods belonging to the VI and VII fundamental groups of foods; they are fruits and fresh vegetables rich in provitamin A (carotenoids), vitamin C and antioxidants.
- Percentage scarcity of cold-pressed vegetable origin seasoning oils; these should make up the majority of dietary lipids, as they are rich in vitamin E and other antioxidants.
- Excessive storage of food in plastic bags, in which bacteria easily convert nitrites into nitrosamines.
Diet to Prevent Gastric Carcinoma
Having clarified the predisposing factors for the formation of gastric cancer, let's define more clearly what are the nutritional principles that help prevent the disease:
- Not more than 25-30% of the total energy from fat.
- Nutritional distribution of fatty acids in favor of the unsaturated ones (at least 15-20% of the total energy) over the saturated ones (not> 10% of the total energy), with a satisfactory polyunsaturated share (5-10% of the total energy) ).
- Not more than 1500mg of total sodium; kitchen salt contains about 40%.
- Elimination of toxic molecules typical of roasting, caramelization, smoking and the surface of food cooked on the grill or on the plate (polycyclic aromatic, acrylamide, acrolein, formaldehyde, etc.).
- Significant reduction of nitrates, nitrites and therefore nitrosamines.
- Elimination of ethyl alcohol or drastic limitation.
- Increase in dietary fiber up to 30g / day.
- Increase in provitamin A, vitamin C and vitamin E.
- Increase of non-vitamin antioxidants (phenolic and non-phenolic).
- Short and optimal conservation of refrigerated foods.
In practical terms, all this translates into:
- Consumption of lean foods of animal origin seasoned with a maximum of 5-10g of raw pressed vegetable oil for each portion (for example extra virgin olive oil)
- As a main course (main course), consume fish 2-3 times a week, meat about 2 times a week, low-fat cheeses 1-2 times and whole eggs once.
- Consume at least 2 portions of fresh vegetables a day, of which at least 50% raw in portions of 50-300g (depending on the type).
- Consume at least 2 servings of fresh fruit per day; portions range from 150 to 300g, depending on the sugar level.
- Consume whole grains and unshelled legumes every day (first courses, side dishes and accompanying bread), in whole form or in foods that contain them (as long as they are not too processed or refined).
- Prefer fresh foods, avoiding those stuffed or preserved in brine or smoked or dried or subjected to salting; furthermore, by avoiding adding salt in cooking and on dishes, this selection will reduce the intake of sodium, nitrates and toxic molecules.
- Cook with indirect systems, such as boiling, steaming, pressure cooking, bain-marie cooking, sous-vide cooking and pot cooking. This will help decrease total fat and toxic molecules.
- Eliminate all hard and empty drinks; eventually, limit yourself to 2 glasses of red wine a day.
- To moderate the introduction of nitrites, consume above all seasonal fruit and vegetables, avoiding greenhouse ones, remove the stem, the external leaves and the petiole; always wash them thoroughly. Remember that summer products contain less than winter ones and that the richest foods are: lettuce, kohlrabi, capuchin lettuce, watercress, chard, radish, horseradish, rhubarb, beetroot and spinach.
- The conservation of fruit and vegetable products must be short and possibly carried out after washing, preferably in paper bags or containers covered with a cloth.
Diet after Gastrectomy or By-Pass
As anticipated, the removal of the stomach (gastrectomy) or part of it, or the formation of a gastro-jejunal bypass, require the subject to respect a specific diet.
Nutritional deficiencies
The stomach has the function of denaturing and starting the digestion of proteins, thanks to the action of hydrochloric acid and the pepsinogen it produces. Furthermore, it secretes the so-called intrinsic factor which allows the absorption of vitamin B12 in the terminal ileum.
We also remember that the absorption of calcium, although occurring in the intestine, is optimized by the presence of proteins in the meal (basically scarce in the post gastrectomy diet) and by the fecal acid pH (generally made possible by acidic stomach juices).
Impairment of the stomach results in incomplete digestion and generalized malabsorption with weight loss. It is therefore strictly advisable to constantly monitor changes in the organism, both macroscopically and clinically (sugars, fats, proteins, vitamins and mineral salts of the blood, immune system, etc.).
Furthermore, we recommend the use of high-calorie and high-protein food supplements, preferably based on free essential amino acids, and to avoid foods that are too rich in fiber (which hinder digestion and absorption).
The following are potentially found: pernicious anemia due to vitamin B12 deficiency, iron deficiency anemia due to a reduction in iron intake (mainly contained in meat and fish) and impaired calcium metabolism due to reduced absorption.
The solution consists of food supplementation or pharmacological administration of nutrients subject to deficiency. For example, vitamin B12 injections, iron supplement or calcium and vitamin D supplementation.
Small Stomach Syndrome
In those who undergo a major resection, small stomach syndrome occurs frequently, which significantly limits food intake due to a sense of premature fullness or pain. This complication can be circumvented by structuring an "open" (non-limiting) diet, with very small and well-divided meals throughout the day, taking care of chewing and clearly separating solids from liquids (for example, avoiding drinking with meals). For those who are particularly affected by this symptom, it is advisable to increase the food intake in the first phase of the day.
Dumping Syndrome
The too rapid passage of the indigestible meal rich in simple sugars can give rise to the so-called sindrome Dumping, manifested by hypotension, tachycardia and dizziness.
In this case, in addition to respecting the principles already mentioned above, it is advisable to eliminate carbohydrates with a high glycemic index (sweets, sugary fruit, jam, etc.), preferring those with slow absorption (pasta, rice, semolina, etc.) to moderate the glycemic-insulin surge.
Diarrhea, Steatorrhea and Biliary Vomiting
Sometimes, in gastrectomy diarrhea occurs, the result of incomplete digestion (sometimes due to too much fiber) and rich in carbohydrates. If so, it might help to make the above changes and moderate your fluid intake in small sips; it is better to avoid the intake of large portions of fruit or vegetables, to be peeled carefully.
In case of steatorrhea (fats in the faeces) caused by poor mixing of foods, the reduction of fats in the diet and the nutritional integration of fat-soluble molecules (vitamin A, vitamin D, vitamin E, vitamin K and essential fatty acids can become very useful. ).
Biliary vomiting is not uncommon, caused by the accumulation of digestive juices from the pancreas and liver in the first portion of the small intestine; the problem is often solved with the breakdown of food into small and frequent meals.
Prohibited Foods
In the diet for stomach resection, the following are prohibited:
- Sweets, especially creams, chocolate and ice cream.
- Mayonnaise and other sauces, especially packaged.
- Drinks with nerves such as: coffee, fermented tea (red and black) and carbonated drinks (orange juice, cola, etc.).
- Whole foods.
- Fatty and / or overcooked meat.
- Fatty fish.
